Paranoid Penguin - Linux VPNs with OpenVPN, Part II

Build a simple, secure VPN connection now!

At this point, I've got good news and bad news. The good news is, you've made it through the most complicated part of OpenVPN configuration: creating a PKI and generating certificates and related files. The bad news is, you've also reached the end of this month's column!

If you can't wait until next time to use these certificates, to get OpenVPN running, you probably can figure out how to do so yourself. See the openvpn(8) man page and the sample configuration files server.conf.gz and client.conf under /usr/share/doc/openvpn/examples/sample-config-files, upon which my examples are based. Good luck!

Mick Bauer ( is Network Security Architect for one of the US's largest banks. He is the author of the O'Reilly book Linux Server Security, 2nd edition (formerly called Building Secure Servers With Linux), an occasional presenter at information security conferences and composer of the “Network Engineering Polka”.



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password authentication

Anonymous777's picture

I wonder about security if I use a certificate on the server and username/password authentication as the only form of client authentication. As far as I understand this still should be much better than PSK because still authentication is done and changing session keys are used afterwards.
But of course a secure password should be chosen (16-32 random chars).

Or do I miss something here?

Duplicated step

Anonymous's picture

Near the end of page 2 you say "You've got two more files to generate..."

openssl dhparam -out keys/dh1024.pem 1024

but the keys/dh1024.pem file has already been generated by the "./build-dh" command (at least on my system - Ubuntu 9.04).

Minor typo?

Anonymous's picture
openvpn --genkey --secret 2.0/keys/ta.key

... should be ...

openvpn --genkey --secret keys/ta.key

since we're working in the "2.0" directory.

Thanks for the great series!


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